The principal investigator, Dr. Richard Wilson, proposes to completely sequence the 4.8 Mb genome of the pathogenic bacterium, Salmonella typhimurium. The approach will be to utilize essentially the same techniques and infrastructure the has been successfully used to sequence large regions of genomes of the yeast, S. cerevisiae, and the roundworm, C. elegans. To avoid extensive clonal map construction, and at the same time provide the community with localized sequence data on a rapid time scale via the Internet, the investigators will utilize 250-750 kb restriction fragments from the genome as starting points for random sequencing. The investigators feel that this approach will simplify assembly of the sequence and provide an ongoing balance between shotgun data production, finishing, and annotation. Once the sequence of the S. typhimurium genome is well underway, they will utilize a whole genome shotgun approach to produce at least one genome equivalent of raw sequence (about 64 percent coverage) for six additional genomes from other members of the family, Enterobacteriaceae. While these genomes will not be sequenced to completion as part of this effort, the principal investigator believes that one-fold coverage of each genome should be sufficient to identify areas of difference between species that could provide clues about the molecular basis of different host ranges and mechanisms of pathogenesis.